The invention relates to an electric switchgear device comprising at least one electric pole-unit comprising a stationary contact part made of conducting material, a movable contact part able to move from a closed position wherein it is in contact with the stationary contact part to an open position wherein the two contact parts are separated. The electric switchgear device comprises an arc chute comprising two parallel side flanges placed on each side of a longitudinal mid-plane, a rear wall, a bottom arcing horn made of conducting material connected to the stationary contact part and extending close to the rear wall. Said bottom arcing horn is surrounded by a periphery made of gas-generating material. The arc chute comprises a stack of separators extending from one side flange to the other, substantially perpendicularly to the longitudinal mid-plane, at least two of the separators comprising a notch extending in the longitudinal mid-plane.